• Journal of the Korea Academia-Industrial cooperation Society
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• v.16 no.3
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• pp.2089-2099
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• 2015

This study examined the relationships between the blood heavy metal (Pb, Hg and Cd) concentration and exposure-related factors. The subjects were 2,042 (male: 953, female: 1,089) who were recruited through a National Health and Nutrition Examination Survey. Differences in the concentrations of mercury were observed in males, whereas females showed differences in lead and cadmium. Analyses of the blood concentrations according to body mass index and waist circumference showed significantly higher concentrations of mercury. In males, high-density lipoprotein cholesterol of dyslipidemia was higher than normal in the blood lead concentration. In females, low-density lipoprotein cholesterol of dyslipidemia was higher than normal in the blood lead concentration. The blood lead and cadmium concentrations of male smokers was higher than non-smokers, and cadmium showed the same results in females. The blood lead levels were higher in male alcohol consumers than non-drinkers. The blood concentrations of mercury and cadmium showed significant differences according to household income. Blood concentrations of heavy metals were closely related to exposure-related factors, and age, smoking, drinking alcohols, obesity, hyperlipidemia, and household income were found to be relevant.

• Clean Technology
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• v.23 no.2
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• pp.172-180
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• 2017

Thermodynamic evaluation indicates that nearly 100% conversion of elemental mercury to oxidized mercury can be attained by HCl of several tens of ppm level at the temperature window of SCR reaction. Cu-, Fe-, Mn-chloride loaded $V_2O_5-WO_3/TiO_2$ catalysts revealed good NO removal activity at the operating temperature window of SCR process. The catalysts with high desorption temperature indicating adsorption strength of $NH_3$ revealed higher NO removal activity. The HCl fed to the reaction gases promoted the oxidation of mercury. However, the activity for the oxidation of elemental mercury to oxidized mercury by HCl was suppressed by $NH_3$ inhibiting the adsorption of HCl to catalyst surface under SCR reaction condition containing $NH_3$ for NO removal. Metal chloride loaded $V_2O_5-WO_3/TiO_2$ catalysts showed much higher activity for mercury oxidation than $V_2O_5-WO_3/TiO_2$ catalyst without metal chloride under SCR reaction condition. This is primarily attributed to the participation of chloride in metal chloride on the catalyst surface promoting the oxidation of elemental mercury.

• Clean Technology
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• v.27 no.3
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• pp.207-216
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• 2021

Major anthropogenic emissions of elemental mercury (Hg⁰) occur from coal-fired power plants, and the emissions can be controlled successfully using NH₃-SCR (selective catalytic reduction) systems with catalysts. Although the catalysts can easily convert the gaseous mercury into Hg²⁺ species, the reactions are greatly dependent on the flue gas constituents and SCR conditions. Numerous deNO_xing catalysts have been proposed for considerable reduction in power plant mercury emissions; however, there are few studies to date of elemental mercury oxidation using SCR processes with MW- and full-scale coal-fired boilers. In these flue gas streams, the chemistry of the mercury oxidation is very complicated. Coal types, deNO_xing catalytic systems, and operating conditions are critical in determining the extent of the oxidation. Of these parameters, halogen element levels in coals may become a key vehicle for obtaining better Hg⁰ oxidation efficiency. Such halogens are Cl, Br, and F and the former one is predominant in coals. The chlorine exists in the form of salts and is transformed to gaseous HCl with a trace amount of Cl₂ during the course of coal combustion. The HCl acts as a very powerful promoter for high catalytic Hg⁰ oxidation; however, this can be strongly dependent on the type of coal because of a wide variation in the chlorine contents of coal.

• Journal of the Korea Academia-Industrial cooperation Society
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• v.22 no.5
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• pp.1-6
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• 2021

Mercury, once released, is not destroyed but accumulates and circulates in the natural environment, causing serious harm to ecosystems and human health. In the United States, sulfur-impregnated activated carbon is being considered for the removal of vapor mercury from the flue gas of coal-fired power plants, which accounts for about 32 % of the anthropogenic emissions of mercury. In this study, a high-efficiency porous mercury adsorption material was developed to reduce the mercury vapor in the exhaust gas of coal combustion facilities, and the mercury adsorption characteristics of the material were investigated. As a result of the investigation of the vapor mercury adsorption capacity at 30℃, the silica nanotube MCM-41 was only about 35 % compared to the activated carbon Darco FGD commercially used for mercury adsorption, but it increased to 133 % when impregnated with 1.5 % sulfur. In addition, the furnace fly ash recovered from the waste copper regeneration process showed an efficiency of 523 %. Furthermore, the adsorption capacity was investigated at temperatures of 30 ℃, 80 ℃, and 120 ℃, and the best adsorption performance was found to be 80 ℃. MCM-41 is a silica nanotube that can be reused many times due to its rigid structure and has additional advantages, including no possibility of fire due to the formation of hot spots, which is a concern when using activated carbon.

• Korean Chemical Engineering Research
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• v.43 no.1
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• pp.170-175
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• 2005

In this study, mercury was removed by $TiO_2$ using fluorescent light and sunlight, instead of UV lamps. A reactor was specially designed to increase the $TiO_2's$ exposure to the light source and to make the rotational speed constant. The contacting surface area between mercury and adsorbents was increased by packing the adsorption bed with mixture of $TiO_2$ and glass beads. The mercury removal efficiency was more than 99% under all light sources tested in this study. The mercury removal efficiency was more than 99% under the fluorescent light or sunlight which is harmless and cheap or free.

• Korean Chemical Engineering Research
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• v.45 no.2
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• pp.183-189
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• 2007

We have investigated the oxidation of gas phase elemental mercury using dielectric barrier discharge (DBD). In the DBD process, active species such as $O_3$, OH, O and $HO_2$ are generated by collisions between electrons and gas molecules. Search active species convert elemental mercury into mercury oxide which is deposited into the wall of DBD reactor because of its low vapor pressure. The oxidation efficiency of elemental mercury has been decreased from 60 to 30% by increasing the initial concentration of the elemental mercury from 72 to $655{\mu}g/Nm^3$. The gas retention time at the DBD reactor has showed the little effect on the oxidation efficiency. The more oxygen concentration has induced the more oxidation of elemental mercury, whereas there has been no appreciable oxidation within pure $N_2$ discharge. It has indicated that oxygen atom and ozone, generated in air condition determine the oxidation of elemental mercury.

• Journal of the Korean Chemical Society
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• v.37 no.5
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• pp.477-482
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• 1993

The determination of trace level mercury in bio-materials has been investigated by the square wave anodic stripping voltammetry (ASV)-technique at glassy carbon electrode. Prior to analysis, the bio-materials were digested with HNO3/H2SO4 mixture and KMnO4 was added to complete the oxidation. The detection limit of the mercury varied greatly with deposition time, deposition potential, pH and stirring rate. When deposition is carried out for 240 sec with 400 rpm stirring at -1.0 volts vs. Ag/AgCl, the detection limit was below $0.5\;ppb\;(2.5{\times}10^{-9} M)$. The method is recommended for trace level mercury analysis of biomaterials because this procedure is time saving and has higher sensitivity.

• Journal of the Korean Society of Food Science and Nutrition
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• v.29 no.3
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• pp.364-368
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• 2000

국내에서 생산된 곡류 9종 416건, 두류 5종 296건 및 서류 2종 156건에 대해 수은 함량은 Mercury Analyzer로, 납, 카드뮴, 비소, 구리, 망간, 아연 등은 습식분해 후 ICP로 분석하였다. 본 연구 결과, 곡류중 중금속 함량[최소~최대(평균),mg/kg]은 다음과 같았다. 수은 0.0001~0.051(0.007), 납 0.01~0.39(0.13), 카드뮴 0.001~0.098(0.023), 비소 0.01~0.38(0.09), 구리 0.06~11.85(1.73), 망간 0.91~39.15(7.47), 아연 1.35~24.15(9.32) mg/kg으로 나타났다. 또한 두류중 중금속 함량(mg/kg)은 수은 0.0002~0.031(0.005), 납 0.01~0.38(0.12), 카드뮴 0.005~0.098(0.030), 비소 0.01~0.37(0.10), 구리 0.03~6.56(2.44), 망간 0.85~22.97(8.16), 아연 2.40~40.18(11.25) mg/kg이었다 서류중 중금속 함량(mg/kg)은 수은 0.002~0.036(0.017), 비소0.01~0.20(0.08), 구리 0.02~2.91(0.84), 망간 0.26~9.48(2.54), 아연 0.35~6.11(2.23)mg/kg이었다. 본 연구에서 얻어진 분석치들은 국내외 다른 연구자들의 분석치와 비슷한 것으로 나타났으며, 이는 우리나라에서 생산된 곡류, 두류, 서류중의 중금속 함유량은 오염된 것이 아닌 자연함유량 수준인 것으로 파악되어 우리나라 사람이 이들 농산물에서 섭취하는 중금속량으로 인한 위해성은 없는 것으로 판단된다. 또한 우리나라 국민이 곡류, 두류, 서류 등을 통해 섭치하는 납, 수은, 카드뮴 등의 중금속 주간섭취량은 FAO/WHO에서 중금속 안전성 평가를 이해 정한 잠정주간섭취혀용량인 PTW1의 0.2~19%를 차지하고 있다.

• Analytical Science and Technology
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• v.23 no.5
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• pp.492-497
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• 2010

In this study, mercury concentrations in freshwater fish from Lake An-dong basin were investigated and were compared with the results of the national freshwater fish monitoring survey. The mercury concentrations of fish from Lake An-dong were in the range of 37~611 ng/g and Korean piscivorous chub, the top predator showed the highest average mercury concentrations, $198{\pm}97\;ng/g$. Most of fish caught from upstream of Lake An-dong were herbivorous and omnivorous, and goby minnow and pale chub showed relatively lower mercury concentrations of $21{\pm}16\;ng/g$ and $33{\pm}24\;ng/g$, respectively. Especially, mercury concentrations of long nosed barbel and largemouth bass caught from Lake An-dong were found to be higher than those of the average of the national survey monitoring data.

• Korean Journal of Food Science and Technology
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• v.3 no.3
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• pp.135-143
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• 1971

In order to find out the degree of mercury contamination of common foodstuffs a series of determination was carried out by a highly sensitive activation analysis and the following results were obtained. 1. Polished rice contained 0.050 ppm of mercury whereas rice bran had 0.095 ppm mercury which was found in other grain in lesser degree. 2. Vegetables and fruits also contained $0.035{\sim}0.190\;ppm$ of mercury with relatively small variations from sample except persimmon which had a considerably higher amount of mercury. 3. Soybean sprout contained an unexpectantly high amount of mercury. 4. Of the animal products chicken and egg contained more mercury than the meat.