• Journal of Environmental Health Sciences
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• v.21 no.1
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• pp.21-28
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• 1995

The removal of heavy metals from synthetic wastewater containing Pb, Cr, Cd using previously washed and dried exhausted coffee was studied varying cohcentration, pH and temperature. All the heavy metals were removed in 3.0 minutes and the removal efficiency was maximum 80~90% with different pH and temperature conditions. The differences in removal efficiency between exhausted coffee and activated carbon under the same conditions were not seen. The removal efficiency was slightly increased with increasing pH in Cd and increasing temperature in Cr, respectively. The batch adsorption kinetics and adsorption equilibrium were examined and described by a first order reversible reaction and Freundlich isotherm, respectively. And the removal of Pb was found to have the best removal efficiency.

• Analytical Science and Technology
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• v.11 no.6
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• pp.452-459
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• 1998

Crosslinked chitin was prepared from epichlorohydrin and chitin which was isolated from waste marin source. The crosslinked chitosan were prepared by the deacetylation of the crosslinked chitin with a strong base. 2,2'-Iminodibenzoic acid-crosslinked chitosan was prepared by reacting 2,2'-Iminodibenzoic acid salt with crosslinked chitosan-Cl which was obtained by chlorination of crosslinked chitosan. The adsorptivity of Pb(II), Cu(II), Cd(II) was studied as a synthetic adsorbent. Experimental results for the adsorption and the recovery characteristics showed that the more pH increase, the more amount of adsorbed metal ion increase. Optimum adsorption time was 1 hr, and adsorption capacity was increased in order of $Cu^{2+}$<$Cd^{2+}$<$Pb^{2+}$, and recovery capacity was increased in order of $Cd^{2+}$<$Cu^{2+}$<$Pb^{2+}$.

• The Korean Journal of Ecology
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• v.16 no.2
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• pp.199-208
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• 1993

To estimate the level of the air pollution in Taejon city, the contents of S, Pb and Cd of the leaves of the roadside trees were deterimined. And we analyzed the relationship between the contents of S, Pb and Cd in the leaves of the roadside trees and traffic volume. The ranges of S, Pb and Cd contents in all the samples were 1.82~4.34 mg/g, 1.95~$246.80{\mu}g/g$ and 2.00~$20.50{\mu}g/g$ respectively. Areas with the high contents of S, Pb and Cd in the leaves were the road from Taejon railroad station to the provincial government, West Taejon crossroad, Taehwa-dong, Kasuwon-dong and Yongmun crossroad.

• The Korean Journal of Food And Nutrition
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• v.11 no.5
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• pp.521-527
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• 1998

Removabilities of heavy metals(Cd and Pb) by the tea materials (barley-tea, corn-tea, jasmin-tea, brown rice-green tea, black-tea, cassia tora-tea, persimmon peel-tea, and rice-tea) in the tea-water were studied in the various conditions ; particle size of tea (20, 40, 70 mesh), concentration of heavy metal (25, 50, 100 ppm) and extraction temperature(20, 30, 50, 100$^{\circ}C$). The removabilities by the tea solids were increased as the particle size decreased, concentration of heavy metal increased, and extracting temperature increased. Of the nine kinds of tea, Cd and Pb removability by jasmin-tea was highest. In addition, heavy metal removability by cassia tora tea was better than that of other tea as extraction temperature was increased.

• Economic and Environmental Geology
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• v.26 no.2
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• pp.175-185
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• 1993

Soils and dusts collected from Changhang smelter area were analyzed for Cu, Pb, Zn, and Cd in order to determine their dispersion pattern and mode of occurrences, and to investigate the pollution level of heavy metals such as Cu, Pb, Zn, and Cd by smelting activity. The soil pH of Changhang area is in the range of 3.7~8.8, and increased with increasing distance from the smelter site. The particles containing heavy metals are several tens of ${\mu}m$ in diameter, and have well crystal form. Samples collected near the smelter show similar particle properties in size, shape, and composition, which means that they could be originated from the same contamination source. Element couples of Cu, Pb, Zn, and Cd indicate high correlation with each other, which means that Cu, Pb, Zn, and Cd could be originated from the same point source of smelter. Heavy metal contents were decayed to background levels from 2.5 kilometer away from the smelter.

• Journal of Plant Biology
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• v.22 no.4
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• pp.107-113
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• 1979

The present study was carried out to estimate the comparative effects of hydroponic heavy metals (Al, Cd, Hg, and Pb) on ATP content in plant leaves grown with Hoagland solution under green house condition. The two plants, kidneybean(Phaseolus vulgaris L.) and buckwheat(Fagopyrum esculentum M nch), showed similar inhibitory effect of heavy metals on ATP content in order of Hg, Cd, Pb, and Al. But the overall inhibitory effect was greater in kidneybean than in buckwheat. The affinity of heavy metals, in vitro, toward the enzyme (luciferin-luciferase) is in order of Hg, Al, Cd, and Pb, similar to that toward ATP. The results showed that the inhibitory effect of heavy metals on ATP hydrolysis is mainly due to the coordination of heavy metals with enzyme than ATP.

• Resources Recycling
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• v.13 no.1
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• pp.22-27
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• 2004

Purification on the leaching solution of the crude zinc oxide obtained by the reduction of EAF dust has been carried out. Pb and Cd ions in the leaching solution were precipitated and removed from the solution by the addition of zinc metal powder. The purification condition for electrowinning to obtain the high purity zinc metal was investigated by analyzing the effects of Pb and Cd ion concentrations on the contents of impurities in the recovered zinc metal. The 3 N purity zinc metal was obtained at the electrolysis condition of the concentrations of Pb less than 2 ppm and Cd less than 0.1 ppm in the purified solution. For this purification, the amounts of zinc metal powder more than 8.5 g/l should be added in the crude zinc oxide leached solution.

• Journal of Korean Society of Occupational and Environmental Hygiene
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• v.21 no.1
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• pp.25-32
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• 2011

Objectives: This study aims to evaluate the dietary intake and blood concentrations for examination of exposure levels and exposure characteristics of Cd and Pb via food among college students aged 20 years living in Busan area. Methods: Food duplicate per a day and venous blood samples were accepted from healthy man and women college students. The samples were analyzed with graphite furnace atomic absorption spectrophotometer. Results: Dietary intake of Cd and Pb in the participants were $17.5{\mu}g\;Cd/day$, $21.7{\mu}g\;Pb/day$. Blood concentrations were $2.01{\mu}g\;Cd/L$, $4.32{\mu}g\;Pb/dL$, respectively. Conclusions: Smoking and drinking habits might be high influential factors in 20 years college students. Dietary intake of Cd and Pb, however, from food group of seaweed, or fish and shellfish in 20 years college students were lower than that in any other age group.

• Journal of Electrochemical Science and Technology
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• v.5 no.4
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• pp.115-127
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• 2014

Cd-Pb thin films were electrodeposited from a diluted chloride solution using stainless steel rotating disc electrode. The linear sweep voltammograms of the single metallic ions show that electrodeposition of these ions was mass transfer control due to the plateau observed for different rotations at concentration (50 and 200 ppm). The voltammograms of binary system elucidate that electrodeposition process always start at cathodic potential located between the potential of individual metals. Currents transients measurements, anodic linear sweep voltammetry (ALSV) and atomic force microscopy (AFM) were used to characterize the electrocryatalization process and morphology of thin films. ALSV profiles show a differentiation for the dissolution process of individual metals and binary system. Two peaks of dissolution Cd-Pb film were observed for the binary system with different metal ion concentration ratios. The model of Scharifker and Hills was used to analyze the current transients and it revealed that Cd-Pb electrocrystalization processes at low concentration is governed by three-dimensional progressive nucleation controlled by diffusion, while at higher concentration starts as a progressive nucleation then switch to instantaneous nucleation process. AFM images reveal that Cd-Pb film electrodeposited at low concentration is more roughness than Cd-Pb film electrodeposited at high concentrated solution.

• Environmental Analysis Health and Toxicology
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• v.18 no.4
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• pp.305-310
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• 2003

A rapid, inexpensive enzymatic method is proposed for indirect water quality testing in terms of heavy metal toxicity. The activity of glucose-6-phosphate dehydrogenase was applied for heavy metal toxicity test as an effective criterion in water quality. The toxicity of Pb (lead) and Cd (cadmium) for water flea, Moina macrocopa, were evaluated for 2-8 days with variables of mobilization ability. And the reproduction impairment of Moina macrocopa were investigated as the parameter of chronic toxicity test for Pb and Cd. As a result, the EC$_{50}$ for immobilization of Moina macrocopa were Pb and Cd were 1.6749 and 0.4683, respectively. The values of reproductive impairment to Moina macrocopa for Pb and Cd were 9.5938 and 8.3264 in EC$_{50}$ A significant alteration of G6PDH (Glucose-6-phosphate dehydrogenase) activity of Moina macrocopa was observed when Cd and Pb were treated in media. The results obtained indicate that G6PDH activity of Moina macrocopa can be used as an indicative parameter in aquatic toxicity tests for heavy metals.als.