• Journal of Environmental Science International
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• v.5 no.2
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• pp.211-220
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• 1996

New thin-and diselena-crown ethers containing two suffer and selenium donor atoms have been prepared. And then, mercury ($Hg^{2+}$) ion-selective electrodes with PVC-plasticizer (STPB) based on some macrocycles as neutral carriers were also made. The electrochemical selectivities for various ions, and the effects for macrocycles, matrix of membranes, ratio of plasticizer to macrowcles, concentration and pH of test solution were investigated on the $Hg^{2+}$ ion-selective electrodes. The 1, 10-diselena-18-crown-6-PVC-STPB (sodium tetraphenylborate) exhibited good linear responses of ${28.2}\pm{0.6}$ decade-1 for $Hg^{2+}$ ion in the conientration ranges of $10^{-2}~10^{-6}$ M $Hg^{2+}$ ion. This electrode exhibited comparatively good selectivities for $Hg^{2+}$ ion in comparison with alkali and alkaline earth metal ions, some heavy metal ions and rare earth metal ion in the range of pH 2.5~6.0. In addition, this electrode was applied as a sensor in the titration of $Hg^{2+}$ ion with $1^-$ ion in water.

• Journal of the Korean Chemical Society
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• v.18 no.3
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• pp.202-209
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• 1974

Polarographic behaviors of copper and cadmium complexes with 2,2'-bipyridine and ethylenediamine in acetonitrile have been investigated by the DC and AC polarography. The reduction processes are estimated as follows; $Cu(II)-bipy. \;complex\;{\longrightarrow^{e^-}_{E_{1/2}\risingdotseq+0.1V}}\;Cu(I)-bipy.\;complex\;{\longrightarrow^{e^-}_{E_{1/2}=-0.43V}}\;Cu(Hg)$$Cu(II)-en.\;complex\;{\longrightarrow^{e^-}}\;Cu(I)-en.\;complex\;{times}\;{\longrightarrow^{e^-}_{E_{1/2}=-0.56V}}\;Cu(Hg)$$Cu(II)-bipy. \;complex\;{\longrightarrow^{e^-}_{E_{1/2}=-0.57V}}\;Cu(I)-bipy.\;complex\;{\longrightarrow^{2e^-}_{E_{1/2}=-0.97V}}\;Cd(I)-bipy\;complex$$Cu(II)-en.\;complex\;{\longrightarrow^{e^-}_{E_{1/2}=+0.05V}\;Cu(I)-en.\;complex{\longrightarrow^{e^-}_{E_{1/2}=-0.92V}}\;Cu(Hg)$ The limiting currents of all steps are controlled by diffusion. The number of ligand and the dissociation constant for Cu(Ⅰ)-bipy. complex were found to be n = 2 and $K_d=(1.5{\pm}0.1){\times}10^{-7}$, respectively.

• Bulletin of the Korean Chemical Society
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• v.28 no.3
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• pp.439-442
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• 2007

A solid state Hg(Au)/HgO reference electrode was prepared utilizing gold amalgam solid particles. Solid fine powder of the gold amalgam was prepared by chemical reduction of Au(III) with NaBH4 followed by reduction of Hg(II) in the presence of gold fine particles. The solid content in the suspension of the gold amalgam particles and fine mercury oxide particles in DMF containing PVC was precipitated by the addition of a large amount of water to give solid Hg(Au)/HgO/PVC mixture. After drying, the mixture was pressure-molded to a physically stable Hg(Au)/HgO composite reference electrode material. The electrochemical characteristics of the electrode as a reference electrode were very similar to an ordinary Hg/HgO reference electrode. The electrode material can be molded and fabricated in any desired shape and size. The surface can be renewed by a simple polishing process whenever contaminated or deactivated. The applicability of the electrode in the electrochemical detection of carbohydrates after anion exchange separation was evaluated.

• Journal of environmental and Sanitary engineering
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• v.22 no.1 s.63
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• pp.29-35
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• 2007

This study was examined adsorption ability of heavy metal Hg(I), Pb(II), and U(Vl) ion use of fruit from schizandra chinensis, The fruits of schizandra chinensis sample used breaking into fragments $50{\sim}100$ mesh. The sample solution was mixed fruits of schizandra chinensis and heavy metal ion. Each heavy metal ion of into solution was quantum analysis with ICP-AES. As the result, each condition of maxium adsorption ability of heavy metal ion was high in the range of pH 5-7, adsorption time was about 15 minutes, and the optimum temperature was $100^{\circ}C$. The heavy metal ion was increased adsorption in order of increasing concentration and in ethanol solution better than in aqueous solution.

• Proceedings of the Korean Society of Dyers and Finishers Conference
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• 2011.03a
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• pp.68-68
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• 2011

A new chemosensor based on rhodamine B (1) for $Hg^{2+}$ and $Cu^{2+}$ was synthesized by one-step condensation reaction of rhodamine B hydrazide and Azo dye. Studying for its fluorogenic and colorimetric behaviors towards various metal ions, extreme sensitivity and selectivity were achieved by the detection of $Hg^{2+}$ and $Cu^{2+}$ over other commonly coexistent metal ions, which were accompanied by ring opening of a rhodamine spirocycle framework. In acetonitrile, the presence of $Hg^{2+}$ and $Cu^{2+}$ induces the formation of a Dye 1-ion complex, which was deduced by spectroscopy.

• Journal of the Korean Electrochemical Society
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• v.11 no.1
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• pp.59-63
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• 2008

Poly (vinylchloride) (PVC) membrane electrodes based on neutral carrier, tetracycline was prepared as an active sensor for Hg(II) ion, and tested in different contents of the potassium tetrakis (4-chlorophenyl) borate (KTpClPB) as lipophilic salt. Bis (2-ethylhexyl) sebacate (DOS), bis(l-butylpentyl) adipate (BBPA), 2-nitrophenyl octyl ether (NPOE) and dibutyl phthalate (DBP) were used as diverse plasticizing solvent mediators. This electrode shows excellent potentiometric response characteristics and display good linearity with log $[Hg^{+2}]$ versus EMF response, over a range of concentrations between $10^{-7}$ and $10^{-3}M$. With 30.8mV/decade Nernstian slope, the detection limit was $6.9{\times}10^{-9}M$ and the response time was less than 20s. The proposed electrode yields very good selectivity for mercury (II) ion over many cations such as alkali, alkaline earth, transition and heavy metal ions. And it shows a very stable potential values in a wide pH range. This reliable electrode prepared was kept at least a month without considerable alteration in their response to Hg (II) ion.

• Journal of Korean Biological Nursing Science
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• v.11 no.2
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• pp.99-104
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• 2009

Purpose: An animal model of pressure ulcers was experimentally-induced with the use of greater trochanter of rats. Methods: Twelve male Sprague-Dawley rats were used in this study and they were randomly divided into 4 groups: Group I (n=3, 120 mmHg, 2 hr), Group II (n=3, 120 mmHg, 3 hr), Group III (n=3, 140 mmHg, 3 hr) and Group IV (n=3, 140 mmHg, 4 hr). The rats were anesthetized with 100 mg/kg of ketamine. The pressure ulcers were induced by using a personally-designed pressing apparatus. After 5 days, the wounds were photographed and excised. Results: After 5 days of induced pressure ulcers, it was observed that Group I and Group II responded with Grade I and Grade II, respectively, while Group III and Group IV responded with Grade III. Conclusion: According to the result of this study, it can be concluded that the pressure ulcers were induced the characteristic grades of pressure ulcer classification by adjusting the degree and the duration of compression.

• Environmental Engineering Research
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• v.21 no.1
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• pp.99-107
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• 2016

The adsorption of inorganic mercury, Hg (II), in aqueous solution has been investigated to evaluate the effectiveness of synthesized gold (Au) nanoparticle-coated silica as sorbent in comparison with activated carbon and Au-coated sand. The synthesis of the Au-coated silica was confirmed by x-ray diffraction (Bragg reflections at $38.2^{\circ}$, $44.4^{\circ}$, $64.6^{\circ}$, and $77.5^{\circ}$) and the Au loading on silica surface was $6.91{\pm}1.14mg/g$. The synthesized Au-coated silica performed an average Hg adsorption efficiency of ~96 (${\pm}2.61$) % with KD value of 9.96 (${\pm}0.32$) L/g. The adsorption kinetics of Hg(II) on to Au-coated silica closely follows a pseudo-second order reaction where it is found out to have an initial adsorption rate of $4.73g/{\mu}g/min/$ and overall rate constant of $4.73{\times}10^{-4}g/{\mu}g/min/$. Au-coated silica particles are effective in removing Hg (II) in aqueous solutions due to their relatively high KD values, rapid adsorption rate, and high overall efficiency that can even decrease mercury levels below the recommended concentrations in drinking water.

• Journal of the Korean Chemical Society
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• v.57 no.3
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• pp.341-351
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• 2013

Zn(II), Cd(II) and Hg(II) complexes with a general composition[$M(L)_2(X)_2$], where L=4-aminopyridine (4AP) and $X=NO_2{^-}$ were prepared under microwave irradiation. The metal complexes were characterized by elemental analyses, molar conductance, IR, Far-IR, electronic, NMR ($^1H$, $^{13}C$), XPS spectral and thermal studies. The spectroscopic studies reveal the composition, different modes of bonding, electronic transition, different chemical environment of C and H atoms and the electronic state of the metal atoms. On the basis of the characterization data, tetrahedral geometry is suggested for all the complexes. The free ligand (4-aminopyridine) and their metal complexes were screened against phytopathogenic fungi and bacteria in vitro and the activities were compared.

• Journal of Microbiology and Biotechnology
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• v.27 no.6
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• pp.1138-1149
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• 2017

The use of microalgal biomass is an interesting technology for the removal of heavy metals from aqueous solutions owing to its high metal-binding capacity, but the interactions with bacteria as a strategy for the removal of toxic metals have been poorly studied. The goal of the current research was to investigate the potential of Burkholderia tropica co-immobilized with Chlorella sp. in polyurethane discs for the biosorption of Hg(II) from aqueous solutions and to evaluate the influence of different Hg(II) concentrations (0.041, 1.0, and 10 mg/l) and their exposure to different contact times corresponding to intervals of 1, 2, 4, 8, 16, and 32 h. As expected, microalgal bacterial biomass adhered and grew to form a biofilm on the support. The biosorption data followed pseudo-second-order kinetics, and the adsorption equilibrium was well described by either Langmuir or Freundlich adsorption isotherm, reaching equilibrium from 1 h. In both bacterial and microalgal immobilization systems in the co-immobilization of Chlorella sp. and B. tropica to different concentrations of Hg(II), the kinetics of biosorption of Hg(II) was significantly higher before 60 min of contact time. The highest percentage of biosorption of Hg(II) achieved in the co-immobilization system was 95% at pH 6.4, at 3.6 g of biosorbent, $30{\pm}1^{\circ}C$, and a mercury concentration of 1 mg/l before 60 min of contact time. This study showed that co-immobilization with B. tropica has synergistic effects on biosorption of Hg(II) ions and merits consideration in the design of future strategies for the removal of toxic metals.