• Korean Journal of Materials Research
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• v.26 no.6
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• pp.298-305
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• 2016

In this work, recent progress on graphene/metal oxide composites as advanced materials for $HgCl_2$ and $CO_2$ capture was investigated. Density Functional Theory calculations were used to understand the effects of temperature on the adsorption ability of $HgCl_2$ and water vapor on $CO_2$ adsorption on CaO (001) with reinforced carbon-based nanostructures using B3LYP functional. Understanding the mechanism by which mercury and $CO_2$ adsorb on graphene/CaO (g-CaO) is crucial to the design and fabrication of effective capture technologies. The results obtained from the optimized geometries and frequencies of the proposed cluster site structures predicted that with respect to molecular binding the system possesses unusually large $HgCl_2$ ($0.1-0.4HgCl_2g/g$ sorbent) and $CO_2$ ($0.2-0.6CO_2g/g$ sorbent) uptake capacities. The $HgCl_2$ and $CO_2$ were found to be stable on the surface as a result of the topology and a strong interaction with the g-CaO system; these results strongly suggest the potential of CaO-doped carbon materials for $HgCl_2$ and $CO_2$ capture applications, the functional gives reliable answers compared to available experimental data.

• Proceedings of the Korean Institute of Electrical and Electronic Material Engineers Conference
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• 2006.11a
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• pp.51-52
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• 2006

FFL의 내구성 및 신뢰성 확보를 위해 Lamp 상태에서 원하는 부위에 $-15^{\circ}C$를 유지하기 위한 Cold Spot을 부착하여 Lamp안의 Hg이 완전히 포집되도록 한다. 이후 이 Cold Spot을 제거하여 Hg peak과 Ne Peak의 Ratio의 변화를 관찰하며 Hg이 이동하는 것을 관잘 하여 Lamp 내에서 이동 속도와 Lamp 간에 이동 속도를 확인 할 수 있다. Lamp 내에서는 80분이 경과한 후에 Hg 이동이 Saturation되는 것을 확인 할 수 있고, Lamp 간에는 100시간이 경과후에 Saturation 되는 것을 확인 할 수 있었고, Ratio는 Channel내는 70 ~ 150, Channel간에는 6~10 정도임을 확인하여 Hg이 이동되는 속도와 회복되는 수준을 알 수 있었다.

• Animal cells and systems
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• v.15 no.3
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• pp.181-187
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• 2011

Transient receptor potential vanilloid type 1 (TRPV1) receptor plays an important role as a molecular detector of noxious signals in primary sensory neurons. Activity of TRPV1 can be modulated by the change in the environment such as redox state and extracellular cations. In the present study, we investigated the effect of the mercury chloride ($HgCl_2$) on the activity of TRPV1 in rat dorsal root ganglia (DRG) neurons using whole-cell patch clamp technique. Extracellular $HgCl_2$ reversibly reduced the magnitudes of capsaicin-activated currents ($I_{cap}$) in DRG neurons in a dose-dependent manner. The blocking effect of $HgCl_2$ was prevented by pretreatment with the reducing agent dithiothreitol (DTT). Inhibition of $I_{cap}$ by $HgCl_2$ was abolished by point mutation of individual cysteine residues located on the extracellular surface of TRPV1. These results suggest that three extracellular cysteines of TRPV1, Cys616, Cys634 and Cys621, are responsible for the oxidative modulation of $I_{cap}$ by $HgCl_2$.

• Journal of Environmental Health Sciences
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• v.13 no.2
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• pp.9-24
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• 1987

This study was conducted to measure the diurnal variation and behaviour of atmospheric mercury in an urban area by gold amalgamation and cold vapour atomic absorption spectrophotometry. The results were as follows: 1. The Hg concentration in ambient air averaged. 21.13ng/m$^3$ for 111 determinations (C.V. 78.5) in urban area and 5.91ng/m$^3$ for 140 determinations (C.V. 21.3) in suburban area. The urban area concentration was significantly higher and fluctuated more than its rural counterpart. 2. Regression analysis of the interaction between mercury concentration and other components showed a significant correlation between mercury concentration and sulfur dioxide also, TSP were found. Mercury concentration was shown to have a similar behaviour, on the whole, with other air pollutants. 3. It demonstrated a positive correlation with sunlight (UV-ray), while it had a negative response to wind speed and humidity. Its concentration showed a tendensy to increase during calm weather specifically. 4. The Hg concentration at the Mt. Dok You inland clean area ranged from 1.33ng/m$^3$ to 2.0ng/m$^3$, with a mean value of 1.63ng/m$^3$.

• Membrane and Water Treatment
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• v.1 no.4
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• pp.231-251
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• 2010

The sulfatation of chitosan, by reaction with chlorosulfonic acid under controlled conditions, allowed increasing the pH range of chitosan solubility. The biopolymer was characterized using FTIR and $^{13}C$-NMR spectroscopy, elemental analysis and titration analysis and it was tested for mercury recovery by polymer enhanced ultrafiltration (PEUF). In slightly alkaline conditions (i.e., pH 8) mercury recovery was possible and at saturation of the polymer the molar ratio $-NH_2$/Hg(II) tended to 2.6. Polymer recycling was possible changing the pH to 2 and the polymer was reused for 3 cycles maintaining high metal recovery. The presence of chloride ions influences metal speciation and affinity for the polymer and "playing" with metal speciation allowed using the PEUF process for mercury separation from cadmium; at pH 11 the formation of hydroxo-complexes of Hg(II) limits it retention. Cake formation reveals the predominant controlling step for permeation flux.

• Advances in nano research
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• v.16 no.1
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• pp.1-9
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• 2024

SiO₂-coated magnetic nanoparticles (Fe₃O₄@SiO₂ NPs) were modified by 3-nitrobenzelidenmalononitrile and used as green linkages for removal of Hg²⁺ form the wastewater. In this research, it has been attempted to refer to the harmful effects of mercury ions for living things and how to remove such ions using very easy and practical technique. This study shows that by optimizing the test conditions, the efficiency of the removal of harmful ions such as mercury from the water contaminated with these ions can be increased. Conditions such as temperature, speed of agitation, pH of solution were tested for removal of mercury ions. The advantages of this method over other methods listed in the article are the rapid and easy nanocry synthesis. The generated and modified Fe₃O₄@SiO₂ nanoparticles were characterized by X-ray diffraction, fourier transform infrared and scanning electron microscopy spectroscopy. The results show that the synthesized magnetic nanoparticles have the excellent performance for the removal of mercury(II) ion from the waste water.

• 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.

• Asian-Australasian Journal of Animal Sciences
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• v.17 no.10
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• pp.1434-1437
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• 2004

The study was conducted to evaluate the effects of montmorillonite anocomposite (MNC) on mercury residues in growing/finishing pigs. A total of 96 cross bred pigs ($Duroc{\times}Landrace{\times}large$ white, 48 barrows and gilts respectively), with similar initial weight (27.87${\pm}$1.15 kg), were used in this study. The animals were randomly assigned to two concentrations of mercury (0.1 and 0.3 ppm from $HgCl_2$) and two levels (0 and 0.3%) of MNC in a $2{\times}2$factorial arrangement of treatments. Each group has 3 pens (replications), and each pen has 8 pigs (4 barrows and 4 gilts). The experiment lasted for 90 days. The results showed that pig growth performances were not affected significantly by inclusion of Hg and addition of MNC (p$\geq$0.05). It indicated that the extent of intoxication in these pigs were not severe enough to impair growth performances. Both on the bases of 0.1 ppm and 0.3 ppm mercury supplementations, addition of 0.3% MNC markedly decreased mercury levels of blood, muscle, kidney and liver tissue (p<0.05). These results implied that the addition of non-nutritive sorptive material, MNC, could effectively reduce the gastrointestinal absorption of mercury via its specific adsorption, with a consequent reduction of mercury residues in body tissues. MNC had offered an encouraging solution to produce safe animal products with mercury contaminated feed.

• Journal of the Korean Chemical Society
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• v.55 no.1
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• pp.38-45
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• 2011

The complexation behavior of the $\alpha$-ketostabilized phosphorus ylides $Ph_3P$=CHC(O) $C_6H_4-X$ (X=Br, Ph) towards the transition metal ions mercury (II) and Silver (I) was investigated. The mercury(II) complex {$HgX_2$ [Y]} 2 ($Y_1$=4-bromo benzoyl methylene triphenyl phosphorane; X=Cl(1), Br(2), I(3), $Y_2$=4-phenyl benzoyl methylene triphenyl phosphorane; X=Cl(4), Br(5), I(6)) have been prepared from the reaction of $Y_1$ and $Y_2$ with $HgX_2$ (X=Cl, Br, I) respectively. Silver complexes [$Ag(Y_2)_2]$ X(X=$BF_4$(7), OTf(8)) of the $\alpha$-keto-stabilized phosphorus ylides ($Y_2$) were obtained by reacting this ylide with AgX (X=$BF_4$, OTf) in $Me_2CO$. The crystal structure of complexes (1) and (4) was discussed. These reactions led to binuclear complexes C-coordination of ylide and trans-like structure of complexes $[Y_1HgCl_2]_2$. $CHCl_3$ (1) and $[Y_2HgCl_2]_2$ (4) is demonstrated by single crystal X-ray analyses. Not only all of complexes have been studied by IR, $^1H$ and $^{31}P$ NMR spectroscopy, but also complexes 1-3 have been characterized by $^{13}$CNMR.

• Journal of the Korean Chemical Society
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• v.14 no.1
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• pp.13-18
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• 1970

非水溶液 Ethylenediamine 中에서 水銀電極의 標準電位 및 水銀鹽化物, $HgCl_2,\;HgBr_2,\;HgI_2$의 Ion-Pair 形成恒數를, Hg電極/$HgX_2$ 또는 $HgX_2$+NaX//亞鉛아마르감 參照電極과 같은 Cell의 構成으로서 電位差法에 依하여 測定하였다.