• Proceedings of the Korean Institute of Electrical and Electronic Material Engineers Conference
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• 한국전기전자재료학회 2004년도 춘계학술대회 논문집
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• pp.47-52
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• 2004

$HgGa_2S_4$ single crystals were grown by the chemical transport reaction method. The $HgGa_2S_4$ single crystal crystallized into a defect chalcopyrite structure $(I\bar{4})$. The lattice constants of the single crystal were found to be a=5.635 ${\AA}$ and c=10.473 ${\AA}$. The direct and indirect optical energy gaps were found to be 2.84 eV and 2.78 eV, respectively. Photoluminescence peaks of $HgGa_2S_4$ single crystal were observed at 2.37 eV, 2.18 eV, and 1.81 eV. In the single crystal, the donor level of 0.25 eV, the acceptor levels of 0.97 eV and 0.41 eV were obtained by TSC, PICTS, and absorption measurements. The photoluminescence peaks were analyzed to relate to the indirect conduction band, the donor level, and the acceptor levels.

• Bulletin of the Korean Chemical Society
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• 제31권12호
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• pp.3707-3710
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• 2010

A chromo/fluorogenic $NO_2S_2$-macrocycle L functionalized with nitrobenzofurazan unit as a dual-signaling probe was synthesized and structurally characterized by single crystal X-ray analysis. In a cation-induced color change experiment, L exhibited excellent $Hg^{2+}$ ion selectivity by showing the color change from orange-red to yellow. However, this hypochromic shift by $Hg^{2+}$ was observed for the weaker coordinating anion system such as ${NO_3}^-$ and ${ClO_4}^-$ ions. The observed anion effect is due to the strong coordination of anions inhibits the bond formation between $Hg^{2+}$ and the macrocyclic tert-N atom, which is sensitive to induce the color change. In the fluorometric experiment, L showed chelate-enhanced fluorescence change effect only with $Hg^{2+}$ ion, together with a change from yellow to green emission. The sensing ability for $Hg^{2+}$ with the proposed chemosensor L is due to the stable complexation with 1:1 stoichiometry (metal-to-ligand).

• Journal of Environmental Science International
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• 제29권2호
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• pp.201-207
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• 2020

A new chemosensor based on a self-assembled system has been devised to detect Hg²⁺ions efficiently. We demonstrated that the amphiphilic building blocks consisting of pyrene and boronic acid (1) aggregate in aqueous solutions and provide an outstanding sensing platform for sensitive detection. The self-assembled 1 exhibited high selectivity and sensitivity for Hg²⁺ion detection via fluorescence quenching, where the Hg²⁺ion detection ensued from a fast transmetallation of 1. The Stern-Volmer (SV) quenching constant for its fluorescence quenching by Hg²⁺ions was approximately 1.58 × 10⁸ M^-1. In addition, self-assembled 1 exhibited excellent sensing abilities at nano-molar concentration levels when tap water and freshwater samples were contaminated with of Hg²⁺ ions.

• Bulletin of the Korean Chemical Society
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• 제35권4호
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• pp.1077-1081
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• 2014

Polyacrylamide (PAM) -HgS nanocomposites were successfully prepared in polyacrylamide (PAM) matrix. From TEM and XRD characterizations, the synthesized HgS nanocrystals were chain-like spherical in shape with a diameter of about 40-60 nm and high crystalline quality. The quantum-confined effect of HgS nanocrystals was confirmed by UV-vis diffuse reflection spectra. The optical properties of products were investigated by using photoluminescence (PL) spectra, which showed that HgS nanocrystals exhibited good optical properties with maximum emission peak at about 640 and 650 nm at different reaction temperatures. The interaction of HgS nanocrystals with PAM was studied through FT-IR spectroscopy and TG analysis, which suggested that $Hg^{2+}$ could interact with functional groups of PAM. The experimental results indicated that PAM not only induced nucleation, but also inhibited further growth of HgS crystals and play an important role in the formation of PAM/HgS nanocomposites. In addition, the possible mechanism of HgS nanoparticles growth in PAM solution was also discussed.

• Bulletin of the Korean Chemical Society
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• 제33권7호
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• pp.2359-2364
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• 2012

Two new chemosensors, rhodamine 6G derivative bearing hydroxyethyl group (1) and rhodamine base derivative bearing 15-crown-5 group (2) were synthesized and their sensing behaviors toward various metal ions were investigated by UV/Vis and fluorescence spectroscopies. Addition of $Hg^{2+}$ ion to a $CH_3CN$ solution of 1 and 2 gave visual color changes as well as fluorescent OFF-ON observations. Selectivity and sensitivity of 1 towards $Hg^{2+}$ are excellent enough to detect micromolar level of $Hg^{2+}$ ion, even in equeous media and biological sample (HeLa cell).

• Neonatal Medicine
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• 제17권1호
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• pp.34-43
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• 2010

Purpose : The aim of this study was to examine whether hypercapnia during the first seven days of life was associated with severe intraventricular hemorrhage (IVH) in preterm infants requiring mechanical ventilation. Methods : A matched pair analysis was performed for 19 preterm infants with severe IVH(grade$\geq$3) and 38 infants with no severe IVH (normal or grade 1), who required mechanical ventilation for more than seven days. The univariate and multivariate analysis of severe IVH with maximal and minimal $PaCO_2$, averag $PaCO_2$, SD of $PaCO_2$, and difference in the $PaCO_2$ were assessed. The major perinatal factors and maximal ventilator index (VI) were also compared. Results : Infants with severe IVH had a higher maximal $PaCO_2$ (86.1$\pm$18.4 mmHg vs. 60.1$\pm$ 11.6 mmHg, P <0.001) and mean $PaCO_2$ (47.5$\pm$5.6 mmHg vs. 41.2$\pm$6.3 mmHg, P=0.004) and a larger SD or difference in $PaCO_2$ (14.0$\pm$4.4 mmHg vs. 9.0$\pm$2.4 mmHg; 60.3$\pm$20.9 mmHg vs. 35.5$\pm$11.8 mmHg, P <0.001). However the minimal $PaCO_2$ values did not differ between the groups. Disseminated intravascular coagulation, pulmonary hemorrhage, and the air leak syndrome were more frequent in the IVH group than in the controls. The maximal VI on each day was higher in the IVH group. The multivariate logistic regression analysis after controlling for bleeding tendency showed that the air leak syndrome, maximal VI, and maximal $PaCO_2$ were independently associated with severe IVH [OR, 1.324 (95% CI, 1.011-1.733; P=0.041)]. Conclusion : Extreme hypercapnia was significantly associated with severe IVH in preterm infants, after adjustment for major perinatal risk factors. Frequent monitoring of the $PaCO_2$ may be important for early detection of inadvertent hypercapnia and prompt correction of high PaCOS levels.

• Korean Journal of Pharmacognosy
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• 제15권4호
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• pp.179-187
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• 1984

To investigate the recorded efficacy in Oriental medical references and effects in clinics, experimental studies were undertaken to estimate 'Palmiwhan' to the diuretic effect in normal rats, rabbits and rats with $HgCl_2-induced$ acute renal failure and hypotensive effects on the nephrogenous hypertension in rabbits with $HgCl_2-induced$ acute renal failure. The results of this study were summarized as follows; Increase in urinary volume, urinary $Na^+\;and\;Cl^-$ excretions were significantly recognized in normal rats and rabbits. Increase in urinary volume, urinary $Na^+\;and\;Cl^-$ excretions were significantly shown in rats with 2mg/kg $HgCl_2-induced$ acute renal failure. Although plasma electrolyte and creatinine levels were little affected, plasma urea nitrogen levels were significantly elevated in normal rats and 2mg/kg $HgCl_2-induced$ acute renal failure of rats. Although the blood pressure was not affected in normal rabbits and cats, hypotensive actions due to the diuretic effect were recognized in rabbits $HgCl_2-induced$ acute renal failure.

• Journal of Preventive Medicine and Public Health
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• 제50권6호
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• pp.377-385
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• 2017

Objectives: Although mercury (Hg) exposure is known to be neurotoxic in humans, its effects on liver function have been less often reported. The aim of this study was to investigate whether total Hg exposure in Korean adults was associated with elevated serum levels of the liver enzymes aspartate aminotransferase (AST), alanine transaminase (ALT), and gamma-glutamyltransferase (GGT). Methods: We repeatedly examined the levels of total Hg and liver enzymes in the blood of 508 adults during 2010-2011 and 2014-2015. Cross-sectional associations between levels of blood Hg and liver enzymes were analyzed using a generalized linear model, and nonlinear relationships were analyzed using a generalized additive mixed model. Generalized estimating equations were applied to examine longitudinal associations, considering the correlations of individuals measured repeatedly. Results: GGT increased by 11.0% (95% confidence interval [CI], 4.5 to 18.0%) in women and 8.1% (95% CI, -0.5 to 17.4%) in men per doubling of Hg levels, but AST and ALT were not significantly associated with Hg in either men or women. In women who drank more than 2 or 3 times per week, AST, ALT, and GGT levels increased by 10.6% (95% CI, 4.2 to 17.5%), 7.7% (95% CI, 1.1 to 14.7%), and 37.5% (95% CI,15.2 to 64.3%) per doubling of Hg levels, respectively, showing an interaction between blood Hg levels and drinking. Conclusions: Hg exposure was associated with an elevated serum concentration of GGT. Especially in women who were frequent drinkers, AST, ALT, and GGT showed a significant increase, with a significant synergistic effect of Hg and alcohol consumption.

• Journal of the Korean Chemical Society
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• 제31권6호
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• pp.534-541
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• 1987

The study of reaction mechanism for the substitution of ethylenediamine (en) for Cl and Hedta from $[CoCl(Hedta)]^-$ in the presence of $Hg^{2+}$ ion was carried out by uv and CD spectra. From the kinetic data, we proposed that the first ethylenediamine be substituted through the associative reaction path by means of interaction of $Hg^{2+}$ ion with Co(III), and that the second and the third ethylenediamine be substituted stepwise. From the optical purities of $[Co(en)_3]^{3+}$ which was formed after reaction, we suggested the critical stereochemical step and new substitution reaction paths.

• Journal of Chest Surgery
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• 제26권11호
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• pp.856-860
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• 1993

We performed serial pulmonary function test and arterial blood gas analysis at preoperative period and postoperative 1st week in 337 patients who underwent pulmonary resection from May 1988 to April 1992 at Dept. of Thoracic and Cardiovascular Surgery, Seoul adventist hospital. Follow-up study for PFT and ABGA were possible in 30 % of the patients at postoperative 3rd or 4th month. In patient who underwent pneumonectomy, VC was decreased from 57.7% to 46.1%, FVC was decreased from 53.5 % to 41.2 % and MBC also decreased from 68.1% to 49.6 % at postoperative 1st week. But ABGA revealed that POa-, was increased from 87.2 mmHg to 92.7 mmHg, and PCO2 was decreased from 43.2 mmHg to 35.9 mmHg at postoperative 1st week. In patients who underwent lobectomy, VC was decreased from 78.1% to 68.30 %, FVC was decreased from 72.5% to 55.3% and MBC was decreased from 73.5% to 68% at postoperative 1st week.But, ABGA revealed that PO2 was increased from 95.2 mmHg to 97.9 mmHg and PCO2 was decreased from 42.3 mmHg to 39.0 mmHg at postoperative 1st week. The pulmonary function recovered at postoperative 3rd or 4th month and its ratio to preoperative value was 90% in lobectomy cases, but in pneumonectomy cases VC and MBC were recovered 20% and 15 % above the preoperative values. We concluded that resection of atelectasis, destructed lung, open negative and open positive cavity in the pulmonary tuberculosis were beni~t to improve ventilation-perfusion ratio,and pulmonary function was recovered nearly to preoperative level at postoperative 3rd or 4th month.