• Journal of dental hygiene science
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• v.15 no.2
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• pp.190-195
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• 2015

The objective of this study is to estimate the relationship between amalgam removal and urinary mercury levels. To measure urinary mercury concentration, urine of participants was collected at baseline, immediately, 24 hours and 48 hours after removal of amalgam restorations. The statistical analysis was performed using IBM SPSS Statistics ver. 20.0. The overall mean urinary mercury concentration at baseline, immediately, 24 hours and 48 hours after removal of amalgam restorations was 2.77, 2.75, 2.95 and $4.00{\mu}g/g$ creatinine, respectively. Logistic regression model shows that the gender leads to increased odds of high urinary mercury concentration in children (odds ratio, OR=1.99), even after adjusting for high amalgam surfaces (OR=1.23) and fish consumption (OR=1.26) at the baseline. Our findings suggest that mercury exposure from dental amalgam adversely impact health and therefore are a health risk.

• Journal of Energy Engineering
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• v.12 no.2
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• pp.65-73
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• 2003

In Korea, not much interest has been paid yet to mercury among flue gas HAPs (Hazardous Air Pollutants), but mercury is expected to become a major problem in the near future. The present paper investigates the current state of mercury emission and control technologies. Interest of the U.S. and European countries in the area of air pollution has been recently directed to mercury emitted from power plants. There are largely two mercury removal technologies applied to power plants. One is removing mercury by oxidizing elemental mercury in WFGD (Wet Flue Gas Desulfurization), and the other is spraying an adsorbent such as activated carbon or other novel sorbents (low-cost sorbents). Developed country is requiring that all power plants be equipped with mercury control facilities by 2007. This paper aims at contributing to the establishment of future strategies in response to the problem.

• 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.

• Environmental engineer
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• s.12
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• pp.38-39
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• 1987

• Journal of Aquaculture
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• v.5 no.2
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• pp.177-182
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• 1992

Experiments were conducted with goldfish exposed to various levels of mercuric chloride(control group) and mercuric chloride with chitosan (experimental group). Dilutions of these two solutions were made in the concentration ranges 0.6 to 1.0 $mg/{\ell}$ and 1.2 to 2.0 $mg/{\ell}$, respectively. Fifty percent lethal concentration of mercuric chloride($LC_{50}$) for 48 hours with the species was between 0.6 and 0.7 $mg/{\ell}$. Exposure of goldfish to mercury produced a marked, dose-dependent mortality with elevation of concentration (P<0.05). However, at each concentration of mercuric chloride treated with chitosan, mortality decreased significantly compared to control group (P<0.05).

• Korean Chemical Engineering Research
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• v.48 no.2
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• pp.268-274
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• 2010

Emission of heavy metals as hazardous air pollutants has been focused with tightening regulatory limits due to their hazardousness. Measurements and characteristic investigations of heavy metals emitted from a commercial power plant burning anthracite coal have been carried out. The plant consists of a circulating fluidized bed combustor, a cyclone, a boiler and an electrostatic precipitator(ESP) in series. Dust and gaseous samples were collected to measure main heavy metals including gaseous mercury before ESP and at stack. Dust emissions as total particulate matter (TPM), PM-10 and PM-2.5 at inlet of ESP were very high with 23,274, 9,555 and $7,790mg/Sm^3$, respectively, as expected, which is much higher than those from pulverized coal power plants. However TPM at stack was less than $0.16mg/Sm^3$, due to high dust removal efficiency by ESP. Similarly heavy metals emission showed high collection efficiency across ESP. From particle size distribution and metal enrichment in sizes, several metal concentrations could be correlated with particle size showing more enrichment in smaller particles. Mercury unlike other solid metals behaved differently by emitting as gaseous state due to high volatility. Removal of mercury was quite less than other metals due to it's volatility, which was 68% only. Across ESP, speciation change of mercury from elemental to oxidized was clearly shown so that elemental mercury was half of total mercury at stack unlike other coal power plants which equipped wet a scrubber.

• Proceedings of the Korea Air Pollution Research Association Conference
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• 2003.11a
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• pp.495-496
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• 2003

연소 배가스 중에 대표적인 가스상 중금속은 수은(Hg), 비소(As), 셀레늄(Se)을 들 수 있다. 이 중에서도 수은은 증기압이 높아서 가스상으로 배출될 가능성이 가장 높은 물질이다. 수은은 세계적으로 약 5000톤이 가스상으로 발생하고 있다. 이 중에서 1000톤은 자연적인 발생원 즉, 화산, 암반이나 해양에서의 증발로부터 발생하며, 나머지 4000톤은 인위적 시설들, 즉 소자로나 발전소, 천연가스, 형광등, 전기제품, 촉매 생산공정 등 일반산업체에서 발생하는 것으로 알려져 있다. (중략)

• Proceedings of the Korea Air Pollution Research Association Conference
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• 2003.11a
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• pp.200-201
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• 2003

최근 들어 미국에서는 석탄 연소배가스 중에 포함된 미량의 중금속이 인체 및 환경에 심각한 피해를 줄 수 있다고 보고 이에 대한 연구를 진행하고 있으며, 특히 수은에 대해서는 SOx, NOx, 먼지와 더불어 배출규제를 시행할 계획을 가지고 있다. 수은배출 규제에 대비하여 미국의 정부산하 연구소와 기업들은 연소 배가스로부터 수은을 제거하기 위한 흡착제 분사, 수은 산화 등 여러 가지 저감기술에 대해 실험실 규모로부터 실증 규모까지 연구를 진행하고 있다. (중략)

• 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.

• Korean Journal of Food Science and Technology
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• v.19 no.6
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• pp.543-549
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• 1987

This study was carried out to estimate the change of Hg content in contaminated food materials including rice grain, soybean sprouts and crucian carp during their washing and cooking processes. The residue level of Hg in contaminated rice at 1 ppm level was decreased to the extent of 24% by three-times washing whereas it was not decreased in cooking. The removal efficiency of Hg in soybean sprouts contaminated at 80 ppm level was about 26% in three-times washing. While the Hg content was not decreased in blanching or cooking of soybean sprouts as a whole, the extent of leached Hg into the fluid part varied in the range of 23-41% depending on the heating time, salinity and volume of cooking water. While the Hg content in fish contaminated at 1 ppm level was not decreased in cooking as a whole, the leaching ratio of Hg into the fluid part was in the range of 2-10% depending on the salinity of cooking water. Disposal of inedible portion in cooked fish could remove 32% of contaminated Hg residue.