• Applied Biological Chemistry
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• v.41 no.4
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• pp.209-212
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• 1998

Methylan, a polysaccharide produced from Methylobacterium organophilum, was chemically modified by adding diethylaminoethyl (DEAE) group to the backbone of methylan. The structure of DEAE-methylan was determined by measuring its nitrogen content obtained from an elemental analysis. From the analysis of mass spectrum, the DEAE group in DEAE-methylan was also confirmed by determining diethylaminoethene as a separate form of DEAE. Mercury adsorption of DEAE-methylan was higher than that of native methylan. This fact was valid for a variety of pH, reaction times, metal concentrations, and polysaccharide concentrations. In particular, native methylan and DEAE-methylan adsorbed 16% (w/w) and 18% (w/w) for mercury after 30 min at pH 7, respectively. The increase in mercury adsorption of DEAE-methylan may be resulted from mercury adsorption by the lone pair electron of nitrogen atom in DEAE group.

• Journal of Environmental Health Sciences
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• v.24 no.1
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• pp.98-103
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• 1998

A study on the removal of mercury and lead by microorganisms, Saccharomyces cerevisiae and Aureobasidium pullulans, was performed, in which the comparison of adsorption model between these two heavy metals was done. The amounts of mercury removed were more than those of lead in both microorganisms. In case of mercury, the adsorption isotherm of S. cerevisiae was accorded with Langmuir model but A. pullulans was followed to Freundlich model. In the case of lead, however, the adsorption isotherm had opposite results. The adsorption rate of mercury to S. cerevisiae was faster than that of A. pullulans, but in the case of lead, it revealed contrary results. It seems, therefore, that the type of microorganisms used as biosorbents should be selected differently with the type of heavy metals removed for applying these to real adsorption process.

• Carbon letters
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• v.2 no.1
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• pp.37-43
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• 2001

Mercury has been identified as a potential health and environmental hazardous material. Activated carbon adsorption offers promising potential for the control of mercury emissions, and sulfur impregnated (sulfurized) activated carbons has been shown to be an effective sorbent for the removal of vapor phase $Hg{\circ}$ from sources. In this work, vapor phase mercury adsorption by sulfur impregnated activated carbons were investigated. Sulfur impregnated activated carbons were made by variation of impregnation temperature, and the comparison of adsorption characteristics with commercial virgin and sulfurized carbons were made. Factors affecting the adsorption capacity of virgin and sulfurized activated carbons such as pore characteristics, functional groups and sulfur impregnation conditions were discussed. It was found that the sulfur allotropes plays a critical role in adsorption of mercury vapor by sulfurized activated carbons.

• Journal of Oral Medicine and Pain
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• v.9 no.1
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• pp.29-33
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• 1984

Dental mercury was injected accidentally to left upper buccal mucosa of a 16-year-old girl by charlatan in order to anesthetize a tooth for extraction; thereafter,injected elemental mercury was almost removed by drug adimnistration and surgical operations.One year have passed, still, there are many scaffered small radiopaque white globular cimages in dental, maxillo-facial, and chest radiographs. Redish swollen gingiva and mobility of left upper central incisor which is adjacent to mercury injection site are oral manifestations in this mercury poisoning case. Recently, the patient complains of metallic taste, gastric discomfort and abdominal pain which are thought to be symptoms of mercury poisoning, but there seems to be no serious sequelae now.

• Journal of Microbiology and Biotechnology
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• v.15 no.3
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• pp.497-501
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• 2005

This study deals with the removal of mercury species using a packed-bed column with spherical aminated chitosan material. These adsorbents revealed a high adsorption capacity for mercury species. Experiments with feed solutions of 10 ppm Hg dissolved in distilled water showed an excellent removal with a sharp increase of the filter effluent concentration after a total throughput of 900 bed volumes of feed water. Up to $95\%$ desorption was reached by using 3 bed volumes of 0.01 N EDTA solution. EDTA could be recovered by means of sulfuric acid with about $75\%$ efficiency. Almost the same results were obtained in repeated sorption and desorption experiments at identical conditions. The experiments demonstrated that the sorbents possessed practically no sorption capacity for alkaline earth ions ($Ca^{2+}\;and\;Mg^{2+}$). Their influence on the sorption of mercury was negligible. In experiments with spiked tap water of the Karlsruhe Research Centre and a feed mercury concentration of 0.01 mg/l, the breakthrough of Hg was observed only after a total throughput of about 6,000 bed volumes of feed water.

• Journal of Electrochemical Science and Technology
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• v.7 no.3
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• pp.241-244
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• 2016

Anodic stripping voltammetry (ASV) is successfully applied in mM level detection of mercury ion in an electroplating bath which is currently used in preparing a cathodic electrolyzer. Glassy carbon electrode is used for the detection and the optimum condition obtained is 10 s deposition at −1.4 V vs. Ag/AgCl and stripping by scanning from −1.4 to +0.4 V vs Ag/AgCl at 50 mV/s. By applying the method, the mercury ion concentration in the electroplating bath could be successfully monitored during the plating.

• Journal of Environmental Health Sciences
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• v.23 no.4
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• pp.21-25
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• 1997

A study on the removal of mercury by Saccharomyces cerevisiae and Aureobasidium pullulans was done, in which the model of adsorption isotherm and adsorption rate was proposed. The adsorption isotherm of mercury by S. cerevisiae was accorded with Langmuir model but A. pullulans was followed to Freundlich model. The amount of mercury removed by A. pullulans was higher than that of S. cerevisiae, but the adsorption rate of mercury by A. pullulans was slower than that of S. cerevisiae. In a rapid adsorption process, therefore, it is more useful to use S. cerevisiae as a biosobent.

• Journal of the Korean Society for Precision Engineering
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• v.17 no.8
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• pp.120-125
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• 2000

This paper proposes a tilt sensor made by MEMS technology. The sensor consists of an electrode glass a small mercury drop a circular channel and a cover glass. The mercury drop is used as medium of a current flow and in contact with two circular chromel electrodes used as an angular-motion resistance When this sensor inclines the mercury drop inside the circular channel moves into the bottom under the influence of gravity. A tilt angle can be measured by changed resistance as tilting this sensor, This sensor has a linear section between +50.$^{\circ}$ and -50.$^{\circ}$ with the accuracy of 2.$^{\circ}$. We are also studying about the enlargement of the linear section and the effect of the size of the mercury drop.

• 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.

• 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.