• Journal of the korean society of oceanography
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• v.33 no.4
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• pp.178-184
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• 1998

To elucidate contamination levels and distribution of methyl mercury (Me-Hg) in Korean coastal areas, 126 sediment samples were collected from Kyeonggi Bay, Namyang Bay, Chinhae Bay, and Lake Shihwa during 1995-1996, and the Me-Hg concentrations were determined by cold vapor atomic fluorescence spectrometry (CVAFS). Contamination levels of Me-Hg in sediments from Kyeonggi Bay, Namyang Bay, Chinhae Bay, and Lake Shihwa were 274 ${\pm}$ 990, 108 ${\pm}$ 24, 294 ${\pm}$ 342, and 1080 ${\pm}$ 760 pg/g, respectively. Concentrations of Me-Hg in sediments were significantly correlated with total organic carbon and sulfur contents, but were independent of mud contents and mean grain size. The highest concentration of Me-Hg (7100 pg/g) was observed at Incheon North Harbor (Site Kl9) in Kyeonggi Bay. This Me-Hg concentration was one or two orders of magnitude higher than those in other Kyeonggi Bay sediments were. The average concentration of Me-Hg in sediments from Lake Shihwa was higher than in those from other study areas. The three peaks of Me-Hg concentrations were observed on three sites (55, 56,and 510) in Lake Shihwa and gradually decreased in distance-dependent manner around these sites. High concentrations of Me-Hg at surface and 10-cm sediment depth in Chinhae Bay maybe due to higher rates of methylation process by active sulfate-reducing bacteria or higher concentrations of total mercury available to sulfate-reducing bacteria.

• Journal of the Korean Society of Food Science and Nutrition
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• v.6 no.1
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• pp.73-79
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• 1977

Heavy metals in the rice and rice paddy soil of Kyung Nam district were surveyed by use of MIBK extraction and atomic absorption spectrophotomter. Mercury was analyzed by nom-flame mercury vapor method. Rice paddy soil showed that cupper amounted to the level of $13.8{\sim}8.4ppm$, average value of 11.5ppm. Lead: $2.6{\sim}0.6ppm$, average 0.02ppm. The conentration of heavy metal $0.04{\sim}0.01ppm$, average 1.5 ppm, Zinc ; $16.1{\sim}7.2ppm$, average 11.3 ppm. Cadmium in rice were containted $2.59{\sim}0.16ppm$ of cupper, average value of 1.80 ppm. Lead: $0.2{\sim}N.D$, Zinc ; $0.11{\sim}0.60ppm$. Cadmium was shown trace at 4 places and mercury was shown trace at 6 places. Cupper showed the highest ratio of heavy metal. Levels in rice and soil whereas zinc showed the highest transmission from soil to rice.

• The Journal of Korea Institute of Information, Electronics, and Communication Technology
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• v.10 no.6
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• pp.477-486
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• 2017

For the analysis of the optical characteristics of electrodeless lamps, all the lamp surface temperatures have been treated the same. However, the interpretation of optical properties in this way has not been sufficient in terms of accuracy. In this paper, to overcome this problem, we divided the inside of the bulb into two parts, hot spot and cold spot, and analyzed the density difference of mercury by different temperatures. Here, it is assumed that the distribution of temperature and density is linear. The effect of optical characteristics through redistribution of hot spot and cold spot density was analyzed. It was also confirmed that the ratio of the density of the redistributed discharge gas has a great influence on the saturation of the optical characteristics. Therefore, it is proved that the design method through the domestic setting is very useful in the actual design, and the method for shortening the time for stabilizing the optical characteristics is obtained.

• Journal of Preventive Medicine and Public Health
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• v.39 no.3
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• pp.199-204
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• 2006

Objectives: Mercury is a hazardous organ-specific environmental contaminant. It exists in a wide variety of physical and chemical states, each of which has unique characteristics for the target organ specificity. Exposure to mercury vapor and to organic mercury compounds specifically affects the CNS, while the kidney is the target organ for inorganic Hg compounds. Methods: In this study, mercury chloride $(HgCl_2)$ was studied in a renal derived cell system, i.e., the tubular epithelial Madin-Darby canine kidney (MDCK) cell line, which has specific sensitivity to the toxic effect of mercury. MDCK cells were cultured for 6-24 hr in vitro in various concentrations (0.1-100 M) of $HgCl_2$, and the markers of apoptosis or cell death were assayed, including DNA fragmentation, caspase-3 activity andwestern blotting of cytochrome c. The influence of the metal on cell proliferation and viability were evaluated by the conventional MTT test. Results: The cell viability was decreased in a time and concentration dependent fashion: decreases were noted at 6, 12 and 24 hr after $HgCl_2$, exposure. The increases of DNA fragmentation were also observed in the concentrations from 0.1 to 10 M of $HgCl_2$ at 6 hr after exposure. However, we could not observe DNA fragmentation in the concentrations more than 25 M because the cells rapidly proceeded to necrotic cell death. The activation of caspase-3 was also observed at 6 hr exposure in the $HgCl_2$ concentrations from 0.1 to 10 M. The release of cytochrome c from the mitochondria into the cytosol, which is an initiator of the activation of the caspase cascade, was also observed in the $HgCl_2-treated$ MDCK cells. Conclusions: These results suggest that the activation of caspase-3 was involved in $HgCl_2-induced$ apoptosis. The release of cytochrome c from the mitochondria into the cytosol was also observed in the $HgCl_2-treated$ MDCK cells. These findings indicate that in MDCK cells, $HgCl_2$ is a potent inducer of apoptosis via cytochrome c release from the mitochondria.

• Proceedings of the KIEE Conference
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• 1989.07a
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• pp.386-389
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• 1989

Phosphorus nitride films on InP surface were grown by a Photo-CVD (chemical vapor deposition) technique over 100-250 $^{\circ}C$ range of substrate temperature, which is based on direct photolysis of $PCl_3/H_2$ and $NH_3$ gas mixtures by 185nm ultraviolet light from a low pressure mercury lamp. The film growth rate ed the refractive index(n) were shown about 700-800 ${\AA}/hr$ and 1.7-1.8, respectively. Composition ratio and interface properties were analyzed by AES(Auger Electron Spectroscopy) and XPS (X-ray Photoelectron Spectorscopy) technique.

• Journal of the Korean Institute of Telematics and Electronics
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• v.26 no.7
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• pp.73-82
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• 1989

We developed a photo-CVD equipment for the deposition of silicon based insulating materials. Silicon dioxide thin films were deposited at various process conditions especially low temperature range $50-250^{\circ}C$. Low pressure mercury lamp was used in the direct excitation of $SiH_4/N_2O$ mixture gas without mercury sensitization. AES and ESCA analysis showed that oxygen to silicon atomic ratio and binding state of Si-O bond was nearly 2.0 and $SiO_2$ type, respectively. The refractive indices were measured to be 1.39-1.44, indicating that films were in relatively low density.

• Journal of Environmental Health Sciences
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• v.37 no.5
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• pp.348-357
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• 2011

Objectives: This study was conducted in order to examine the relationship between heavy metal concentrations in the soil and the level of heavy metals in the blood or urine of 216 local residents living near abandoned metal mines. Methods: Residents around abandoned metal mines were interviewed about their dietary habits, including seafood consumption, medical history, cigarette smoking, and drug history. Metal concentrations in the soil were determined by atomic absorption spectrophotometer (AA-7000, Shimadzu, Japan). Lead (Pb) and cadmium (Cd) contents in the blood or urine were analyzed by GF-AAS (AA-6800, Shimadzu). Mercury (Hg) contents in the blood were determined by means of a mercury analyzer (SP-3DS, NIC). Arsenic (As) content in the soil and urine were measured by a HG-AAS (hydride vapor generation-atomic absorption spectrophotometer). Results: The heavy metal concentrations in the soil showed a log normal distribution and the geometric means of the four villages were 8.61 mg/kg for Pb, 0.19 mg/kg for Cd, 1.81 mg/kg for As and 0.035 mg/kg for Hg. The heavy metal levels of the 216 local residents showed a regular distribution for Pb, Cd, Hg in the blood and As in the urine. The arithmetic means were 3.37 ${\mu}g$/dl for Pb, 3.07 ${\mu}g$/l for Cd and 2.32 ${\mu}g$/l for Hg, 10.41 ${\mu}g$/l for As, respectively. Conclusions: As a result of multi-variate analysis for the affecting factors on the bodily heavy metal concentrations, gender and concentration in the soil (each, p<0.01) for blood lead levels; gender and smoking status (each, p<0.01) for blood cadmium levels; gender (p<0.01) for urine arsenic levels; gender, age and concentration in the soil (p<0.01) for blood mercury levels were shown to be the affecting factors.

• Journal of the Korean Chemical Society
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• v.35 no.4
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• pp.355-361
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• 1991

The separative preconcentration of trace mercury[Hg(II)] in a water sample was studied by a coprecipitation flotation technique. The trace Hg(II) was precipitated together with Ce(OH)$_3$ by adding 3.0 ml of 0.1M Ce$^{3+}$ solution to 1,000 ml of water sample and adjusting pH to 11.0 with 1.0M NaOH solution. The hydrophobic precipitate[Ce(OH)$_3$-Hg(OH)$_2$], which was formed by adding 2.0 ml of 0.1${\%}$ ethanolic sodium oleate solution, were floated on the surface with an aid of tiny nitrogen gas bubbles. The floated materials were quatitatively collected in a suction flask and dissolved with 5.0 ml of 2.0M HNO$_3$. The solution was marked to 25.00 ml with a deionized water. The content of Hg(II) was determined by cold vapor atomic absorption spectrophotometry. Any interferences of concomitants such as Ag$^+$, Br$^-$, I$^- $, etc. were not observed on the whole procedure. The analytical result showed that Hg(II) found in the wastewater of Seochang Campus, Korea University was 1.98 ng/ml with the relative standard deviation of 3.6${\%}$. And recoveries of Hg(II) in the wastewater into which 1.0 ng/ml and 2.0 ng/ml were added were 95${\%}$ and 91${\%}$, respectively. From such results, this procedure could be concluded to be tolerably accurate and reproducible for the determination of trace mercury in a water sample.

• Journal of Sensor Science and Technology
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• v.19 no.5
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• pp.398-402
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• 2010

The liquid phase epitaxy(LPE) method was widely used to growth of mercury cadmium telluride(MCT) thin films. However, this method lead to Hg-vacancies in MCT thin film, because Hg has high vapor pressure at this temperature range. This is a well known defect in HgCdTe grown by LPE method. In this study, we report the development of techniques for improving the crystalline quality and controlling the composite uniformity of HgCdTe thin films using high- pressure Hg-ambient annealing method. As a result, we achieved the improvement of the composite uniformity of HgCdTe thin films. It was observed by the high angle annular dark field scanning TEM(HAADF-STEM) analysis. Moreover, new HgTe phase and a shrinking of lattice fringe were observed.

• Journal of Korea Technical Association of The Pulp and Paper Industry
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• v.41 no.2
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• pp.55-63
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• 2009

This study was performed to evaluate the heavy metal contents in various packaging board. Domestic and foreign OCC (old corrugated containers) and old duplex boards were used as raw materials. Tests were made for the printed and unprinted parts of the sample. Heavy metal contents of old food packaging boards made from virgin pulp fibers were also evaluated. The contents of heavy metals including lead (Pb), cadmium (Cd), barium (Ba), arsenic (As), antimony (Sb), selenium (Se), and mercury (Hg) were determined using ICP-AES (Inductively Coupled Plasma - Atomic Emission Spectrometer), and CV-AAS (Cold vapor-atomic absorption spectrometer) after digesting the samples in a microwave oven. The contents of heavy metals contained in domestic packaging board were higher than those in overseas samples, and OCC showed higher contents of heavy metals than old duplex boards. Printed parts gave greater heavy metal contents than unprinted parts. Results indicate that recycling of paper and paperboard products increases the heavy metal contamination of the paper packaging products and this derives mostly from the heavy metals contained in printing inks. Recycling processes that decrease heavy metals in recycled fibers and new printing inks that contains less heavy metals should be developed to solve the problem associated with the heavy metals in packaging paper products.