• Analytical Science and Technology
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• v.20 no.5
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• pp.419-423
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• 2007

Environmental low level tritium analysis was studied using liquid scintillation counter(LSC) and electrolytic enrichment method. To obtain low level blank count, various counting vials were investigated. Among them, teflon coated PE vial had a lower blank count rate (1.86 cpm) and we obtained 2.01 Bq/L detection and tritium separation factor was above 20. LSC counting efficiency obtained $28.70{\pm}0.27%$ using the NIST tritium standard water sample.

• Journal of Radiation Protection and Research
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• v.21 no.2
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• pp.107-115
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• 1996

An electrolytic enrichment technique was used to measure low levels of tritium in seawater around the Korean peninsula. Tritium concentrations were determined for surface seawater samples collected from the East Sea, the South Sea, and the Yellow Sea. The tritium concentrations in surface seawater samples from the study area ranged from $0.12 BqL^{-1}\;to\;1.50BqL^{-1}$ with a mean value of $0.60{\pm}0.35 BqL^{-1}$. The means of the tritium concentration were $0.54{\pm}0.30 BqL^{-1}$ for the East Sea, $0.48{\pm}0.35 BqL^{-1}$ for the South Sea, and $0.77{\pm}0.32 BqL^{-1}$ for the Yellow Sea. The tritium concentrations in the sea areas did not show much difference no matter where the samples were taken. Due to the limited number and distribution of sampling points, no systematic change in tritium levels with latitude was observed. Measured tritium levels were similar to those observed in other data collected near Japan, but higher than mid-Pacific Ocean measurements.

• Resources Recycling
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• v.21 no.6
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• pp.39-44
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• 2012

An attempt to recover copper from electroless plating wastewater has been made through evaporation followed by the electrowinning method. From the determination of each element in electroless plating wastewater, the content of Cu was found to be 582 mg/l and small amount of Fe was also contained in it. Moreover, the content of COD and TOC which was resulted from the addition of Rochell salt was found to be 9,560 and 13,100 mg/l, respectively. The content of formic acid generated by the oxidation of formaldehyde was determined to be 7.73 %. As a result, current efficiency was decreased with increase in current density and therefore current density less than $40mA/cm^2$ should be maintained to obtain current efficiency more than 80 %. The content of Fe in Cu obtained by electrowinning was found to be 0.021 and 0.01 % at the concentration of sulfuric acid of 2 and 10 vol%, respectively.

• Journal of the Korean Chemical Society
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• v.42 no.1
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• pp.28-35
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• 1998

Microorganisms such as alga are able to uptake toxic and heavy metal ions. After Cd(Ⅱ) was preconcentrated on the carbon paste electrode constructed by incorporating alga (Anabaena), it was determined with differential pulse anodic stripping voltammetry. A well-defined oxidation peak of Cd(Ⅱ) was obtained at - 0.75 V vs. SCE. We investigated the optimum conditions using the peak, which are the effect of the amount of alga, pH, ionic strength, temperature, and preconcentration time on the preconcentration of Cd(Ⅱ) and that of the reduction time and potential on the reduction of Cd(Ⅱ) preconcentrated. Calibration curve for the determination of Cd(Ⅱ) was linear over the range of $1.0{\times}10^6\;M\;to\;8.0{\times}10^6$\;M (R=0.9978) and the detection limit was $5.0{\times}10^{-7}$\;M. The relative standard deviation was 3.1% (n=6) for $7.0{\times}10^{-6}\;M Cd(Ⅱ). In regeneration of the electrode surface with 0.1 M HCl, the response was reproducible continuously by 10 times.

• Nuclear Engineering and Technology
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• v.10 no.1
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• pp.13-25
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• 1978

The present paper deals with the measurement of the environmental radioactivity at the Kori nuclear Power Plant site area for the Period of six years from December 1970 to December 1976. Gross alpha activity was measured in samples of airborne particulate. Gross beta measurement was performed on soil, water, airborne perticulate, pine needle, precipitation, fallout (gummed acetate paper) and various foodstuffs. Radioactivities of strontium-90 and cesium-l37 were determined by means of radiochemical analyses in samples of spinach, cabbage, barley, rice in terrestrial food, sea eel, shell fish, dulse, green laver in marine product and milk, and of fallout (cloumn), Furthermore, tritum was also analyzed in water sample of well, stream and sea by electrical enrichment.

• Journal of the Korean Chemical Society
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• v.41 no.4
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• pp.180-185
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• 1997

Zinc, cadmium, lead and copper were simultaneously determined by depositing metals at - 1.200 V vs. a Ag/AgCl(sat. KCl) reference electrode for 150 seconds on a hanging mercury drop electrode(HMDE) or a thin mercury film electrode(TMFE), followed by scanning towards anodic direction using differential pulse voltammetric(DPASV) and square wave voltammetric(SWASV) techniques. The linear calibration curves were obtained for four metal ions simultaneously determined by DPASV with a HMDE in the concentration range between 20 and 100 ppb. However, the linear calibration plots were obtained only for $Cd^{2+}$ and $Pb^{2+}$ in the simultaneous determinations with a TMFE in the concentration range up to 100 ppb using DPASV and up to 10 ppb using SWASV. DPASV with a TMFE was about 15 times more sensitive than DPASV with a HMDE for simultaneous determinations of $Cd^{2+}$ and $Pb^{2+}$. SWASV was about 5 times more sensitive than DPASV at a TMFE. Concentrations of zinc in seven different sediment samples determined by DPASV with a HMDE and inductively coupled plasma-mass spectrometry were compared, resulting with an excellent correlation coefficient of 0.9993 and with no significant difference between two methods after t-test.