• Bulletin of the Korean Chemical Society
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• v.23 no.2
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• pp.346-350
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• 2002

A glassy carbon electrode (GCE) modified with 2,2':6':2”-terpyridine (2,2':6':2”-TPR) using a spin coating method was applied for the highly selective and sensitive analysis of a trace amount of $Hg_2^{2+}$ ions. Various experimental parameters, which influenced the response of the 2,2':6':2”-TPR modified electrode to $Hg_2^{2+}$ ions, were optimized. The linear sweep and differential pulse voltammograms for the 2,2':6':2”-TPR modified electrode deposited with Hg show a well-defined anodic peak at +0.65 V (vs. Ag|AgCl). After a 25 min preconcentration time in an $Hg_2^{2+}$ ion solution (0.1 M acetate buffer, pH 5.0), differential pulse voltammetry(DPV) with 2,2':6':2”-TPR modified electrode shows a linear response between $1.0\;{\times}\;10^{-6}M\;and\;2.0\;{\times}\;10^{-7}M$. The least-square treatment of these data produce an equation of I[${\mu}A$] = 0.031 + 0.005C with r = 0.980(n = 5). The detection limit of this electrode with linear sweep voltammetry and differential pulse anodic voltammetry were $2.0\;{\times}\;10^{-6}M\;and\;8.0\;{\times}\;10^{-8}M$, respectively. The presence of Pb, Fe, Cd, Ti, Ni, Co, Mg, Al, Mn, and Zn did not interfere in the analysis of the $Hg_2^{2+}$ ion. The 2,2':6':2”-TPR modified GCE has been successfully applied in determination trace amounts of Hg in a human urine sample.

• Journal of the Korean Society of Radiology
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• v.8 no.7
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• pp.383-387
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• 2014

In this paper, for a new detection system development with the better accurate dose evaluation and beam distribution imaging using the small field irradiation of linear accelerator, the compound semiconductor based detection sensors were fabricated and the performance evaluation was investigated. The special particle-in-binder sedimentation was used for a large area film sensor fabrication. The detection properties for high energy x-rays were investigated from a dark current, an output current, a rising time, a falling time, and response delay measurement. The experimental results, the $TiO_2$ mixed $HgI_2$ sensor showed the best electrical characteristics than $PbI_2$, PbO, pure $HgI_2$. Linearity, repeatability, and accuracy tests from LINAC were tested, the $TiO_2$ mixed $HgI_2$ sensor showed the better performance than the commercially available dosimetry devices.

• Journal of the Korean Chemical Society
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• v.51 no.4
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• pp.324-330
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• 2007

A new ion selective PVC membrane electrode is developed as a sensor for mercury(II) ions based on bis(benzoylacetone) propylenediimine (H2(BA)2PD) as an ionophore. The electrode shows good response characteristics and displays, a linear Emf vs. log[Hg2+] response over the concentration range of 1.0×10-6 to 1.0×10-1 M Hg(II) with a Nernstian slope of 29.8±0.75 mV per decade and with a detection limit of 2.2×10-7 M Hg(II) over the pH range of 2.5-11.5. Selectivity concentrations for Hg(II) relative to a number of potential interfering ions were also investigated. The sensor is highly selective for Hg(II) ions over a large number of cations with different charge. The sensor has been found to be chemically inert showing a fast response time of 60 s and was used over a period of 3 months with a good reproducibility (S = 0.27 mV). The electrode was successfully applied to determine mercury(II) in real samples with satisfactory results.

• Bulletin of the Korean Chemical Society
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• v.35 no.11
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• pp.3326-3330
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• 2014

A quinoline-thiooxorhodamine conjugate fluorescent sensor (1) has been synthesized. Sensor 1 exhibits high selectivity and sensitivity to $Hg^{2+}$ in $H_2O$/DMSO (95/5, v/v, HEPES 20 mM, pH = 7.4) solution with fluorescence detection. Other tested metal ions do not induce any significant fluorescence intensity changes. Sensor 1 interacts with $Hg^{2+}$ through a 1:1 binding stoichiometry with a good anti-inference ability. In addition, fluorescent imaging of $Hg^{2+}$ in Hela cells is also successfully demonstrated.

• Textile Coloration and Finishing
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• v.27 no.4
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• pp.261-269
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• 2015

Two new D-${\pi}$-A dyes were synthesized by the condensation reaction between active methyl and aromatic aldehyde and its biothiol sensing properties in DMSO/water were investigated by UV-vis spectroscopy. Upon addition of $Hg^{2+}$, the solution of D-${\pi}$-A dyes showed color change and the absorption band shows a formation of a dye-$Hg^{2+}$ coordination complex. These dyes exhibited high selectivity for $Hg^{2+}$ as compared with other cations. The dye-$Hg^{2+}$ could be recovered by adding glutathion(GSH). The absorption intensity of dye-$Hg^{2+}$ increased only by the addition of glutathione(GSH). The competition experiments revealed that no obvious interference was observed by performing the titration with the mixture of glutathione(GSH) and other amino acids. The results indicated that these D-${\pi}$-A dyes were highly selective for glutathione(GSH) detection.

• Microbiology and Biotechnology Letters
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• v.27 no.4
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• pp.278-285
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• 1999

In order to use heat shock promoter for the detection of toxic substances, dnaK promoter was amplified from E. coli genomic DNA by using a polymerase chain reaction(PCR) followed by sequencing and sub-cloning into the multi-cloning site of the plasmid, pUCD615. The pUCD615 is a broad-host-range vector containing promoterless lux operon originated from V.fischeri. The recombinant plasmid was transfered to E. coli DH5$\alpha$ through electroporation. The recombinant E. coli showed several patterns of bioluminescent responses to ethanol stress. The bioluminescent E. coli also showed responses to other toxic substances including FeK3(CN)6, CdCl2, p-nitrophenol and HgCl2. The increases of RLU(Relative Light Unit) were observed at 100ppm of FeK3(CN)6, 10ppm and 100ppm and 100ppm of CdCl2, 1ppm of 10ppm of p-nitrophenol and at 1ppm of HgCl2.

• Bulletin of the Korean Chemical Society
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• v.33 no.12
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• pp.4219-4222
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• 2012

• Bulletin of the Korean Chemical Society
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• v.31 no.10
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• pp.2949-2954
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• 2010

Ionic liquid-functionalized ordered mesoporous silica SBA-15 modified carbon paste electrode (CISPE) was fabricated and its electrochemical performance was investigated by cyclic voltammetry, electrochemical impedance spectra. The electrochemical behavior of $Cd^{2+}$, $Pb^{2+}$, $Cu^{2+}$ and $Hg^{2+}$ at CISPE was studied by differential pulse anodic stripping voltammetry (DPASV). Compared with carbon paste electrode, the stripping peak currents had a significant increase at CISPE. Under the optimized conditions, the detection limits were $8.0{\times}10^{-8}\;M$ ($Cd^{2+}$), $4.0{\times}10^{-8}\;M$ ($Pb^{2+}$), $6.0{\times}10^{-8}\;M$ ($Cu^{2+}$), $1.0{\times}10^{-8}\;M$ ($Hg^{2+}$), respectively. Furthermore, the present method was applied to the determination of $Cd^{2+}$, $Pb^{2+}$, $Cu^{2+}$ and $Hg^{2+}$ in water samples and people hair sample.

• Proceedings of the Korean Institute of Electrical and Electronic Material Engineers Conference
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• 2004.11a
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• pp.456-459
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• 2004

Analog film/screen systems have been being changed to a digital x-ray imaging device using direct conversion materials. Photocoductors for a direct detection flat-panel imager require high x-ray absorption, ionization and charge collection, low leakage current and large area deposition. In this work, $HgI_2$ films with excellent properties for x-ray detector were deposited by screen printing method. The thickness of $HgI_2$ film was about $150\;{\mu}m$. The passivation layer is fabricated using a-Se and parlyene, the both fabrication $HgI_2$ film were compared for analyzing the leakage current reduction. We measured electrical properties-leakage current, photosensitivity, SNR though I-V measurement, As the result, $HgI_2$ film using a-Se passivation layer had the greater

• Proceedings of the Korea Technical Association of the Pulp and Paper Industry Conference
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• 2006.06b
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• pp.465-469
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• 2006

Pre-treatment methods to determine various heavy metal contents in packaging papers were investigated by ICP-ES (Inductively Coupled Plasma Emission Spectrometry) analysis. Pre-treatment methods utilized in this study include dry ashing and decomposition methods ($HNO_{3-}HClO_{4-}HF,\;HNO_{3},\;and\;H_{2}SO_{4-}HNO_{3}$). They were compared with the conventional extraction (water) and migration (3% acetic acid) methods. The five representative heavy metals (Cd, As, Pb, Cr and Hg) were analyzed. For Cd, Hg, and As, the results were below detection limit of the instrument. In case of Cr and Pb, the migration test is considered to be a better method compared to the extraction test, but all pretreated methods showed much higher detection efficiency than the extraction or migration test. However, the detection ratio between the migration test and decomposition methods was different. Among all decomposition methods, the nitric acid - perchloric acid - hydrofluoric acid treatment brought a slightly higher detection value than others, but there was no significant difference among them except sulfuric acid - nitric acid method. Concerning Pb, the sulfuric acid - nitric acid method showed a low detection efficiency compared to other decomposition methods. The sulfuric acid - nitric acid method is, thus, not considered to be a suitable analysis method for Pb in packaging papers.